1. Field of the Invention
The present invention relates to a vacuum breaker having a universal inlet port, a one port embodiment for handling a single high rate fluid flow, and a two port embodiment for handling a plurality of low rate fluid flows, as in a dialysis unit application for venting to atmosphere both patient waste fluids and reverse osmosis (RO) waste water, the vacuum breaker further having a universal mounting arrangement for location of the vacuum breaker inside the upper ends of either relatively small or relatively large standard size waste standpipes.
2. Description of the Prior Art
Prior art vacuum breakers that discharge into a waste standpipe usually are mounted by forcing them onto the upper end of the standpipe, deforming the material of which the vacuum breaker is made to provide a clamping action. This makes them susceptible to tipping and inadvertent detachment. Furthermore, the clamping force must be overcome to remove them from the standpipe, which slows the process of removing one vacuum breaker and substituting another. This is a particular problem in an installation where a plurality of vacuum breakers are in use, such as in an installation comprising many dialysis units.
Dialysis units perform a well known function in various applications. In particular, such a unit filters the blood, essentially performing for the dialysis patient that which the kidneys do in a healthy individual. The kidney cleansing procedure generates both patient waste fluids and reverse osmosis (RO) waste fluid, the integral RO unit being present to facilitate proper operation of the dialysis unit.
In a dialysis unit the discharge lines from the patient's body fluids and the RO waste water both empty into the same waste standpipe. Where several dialysis units are combined in a single installation, the discharge lines empty into separate waste standpipes, with each unit being periodically removed upon completion of the cleansing procedure for replacement by another.
The discharge lines are commonly secured within each waste standpipe by means of screw clamps or banding. These must be individually tightened to prevent inadvertent separation. Tedious mounting procedures are time consuming. This poses a serious problem where only one nurse or medical assistant is available for servicing several dialysis units. The mounting or attachment means must also fit onto waste standpipes of at least the two most standard sizes, i.e. 11/2 inches and 2 inches in diameter.
A need exits for a vacuum breaker that can be fitted quickly and easily onto standpipes and just as readily be detached when necessary.
Vacuum breakers are known for venting waste water flow from a reverse osmosis unit, but applicant is not aware of any vacuum breaker that operates like two separate vacuum breakers to simultaneously drain and vent RO waste water and patient fluids from a dialysis unit.
It is common to vent water flowing at a high rate from a washing machine, dishwasher or water softener, as disclosed in U.S. Pat. No. 3,411,524 for "Vacuum Breaker", invented by Robert E. Raine and applicant. However, nothing comparable appears to exist for venting two different fluid streams with a single vacuum breaker, and that acts like two separate vacuum breakers to achieve simplicity of operation, reduced cost and ease of installation. Somewhat analogous but far from similar devices are disclosed in my U.S. Pat. Nos. 5,592,964 and 5,176,165.